Ecological succession of the microbial communities of an air-conditioning cooling coil in the tropics.

Air-conditioning systems harbor microorganisms, potentially spreading them to indoor environments. While air and surfaces in air-conditioning systems are periodically sampled as potential sources of indoor microbes, little is known about the dynamics of cooling coil-associated communities and their effect on the downstream airflow. Here, we conducted a 4-week time series sampling to characterize the succession of an air-conditioning duct and cooling coil after cleaning. Using an universal primer pair targeting hypervariable regions of the 16S/18S ribosomal RNA, we observed a community succession for the condensed water, with the most abundant airborne taxon Agaricomycetes fungi dominating the initial phase and Sphingomonas bacteria becoming the most prevalent taxa toward the end of the experiment. Duplicate air samples collected upstream and downstream of the coil suggest that the system does not act as ecological filter or source/sink for specific microbial taxa during the duration of the experiment.

Cascade of magnetic field induced spin transitions in LaCoO3.

We present magnetization and magnetostriction studies of LaCoO3 in magnetic fields approaching 100 T. In contrast with expectations from single-ion models, the data reveal two distinct first-order transitions and well-defined magnetization plateaus. The magnetization at the higher plateau is only about half the saturation value expected for spin-1 Co3+ ions. These findings strongly suggest collective behavior induced by interactions between different electronic configurations of Co3+ ions. We propose a model that predicts crystalline spin textures and a cascade of four magnetic phase transitions at high fields, of which the first two account for the experimental data.

Recommendations for standardization and phenotype definitions in genetic studies of osteoarthritis: the TREAT-OA consortium.

OBJECTIVE: To address the need for standardization of osteoarthritis (OA) phenotypes by examining the effect of heterogeneity among symptomatic (SOA) and radiographic osteoarthritis (ROA) phenotypes. METHODS: Descriptions of OA phenotypes of the 28 studies involved in the TREAT-OA consortium were collected. We investigated whether different OA definitions result in different association results by creating various hip OA definitions in one large population based cohort (the Rotterdam Study I (RSI)) and testing those for association with gender, age and body mass index using one-way ANOVA. For ROA, we standardized the hip-, knee- and hand ROA definitions and calculated prevalence's of ROA before and after standardization in nine cohort studies. This procedure could only be performed in cohort studies and standardization of SOA definitions was not feasible at this moment. RESULTS: In this consortium, all studies with SOA phenotypes (knee, hip and hand) used a different definition and/or assessment of OA status. For knee-, hip- and hand ROA five, four and seven different definitions were used, respectively. Different hip ROA definitions do lead to different association results. For example, we showed in the RSI that hip OA defined as "at least definite joint space narrowing (JSN) and one definite osteophyte" was not associated with gender (P =0.22), but defined as "at least one definite osteophyte" was significantly associated with gender (P=3×10(-9)). Therefore, a standardization process was undertaken for ROA definitions. Before standardization a wide range of ROA prevalence's was observed in the nine cohorts studied. After standardization the range in prevalence of knee- and hip ROA was small. CONCLUSION: Phenotype definitions influence the prevalence of OA and association with clinical variables. ROA phenotypes within the TREAT-OA consortium were standardized to reduce heterogeneity and improve power in future genetics studies.

Generation of orthogonal codes with chaotic optical systems.

We propose to use an electro-optic oscillator based on two Mach-Zehnder modulators in two different delayed feedback loops to generate two orthogonal chaotic spreading sequences (codes). We numerically demonstrate, for such codes, spectrally efficient multiplexing and demultiplexing of two digital data streams at multi-Gb/s rates using chaos synchronization and covariance-based detection.

Discovery of cockroach specimens of the genus Squamoptera (Ectobiidae: Pseudophyllodromiinae) from Okinawa, Japan, showing wing polymorphism.

Cockroach specimens of the genus, Squamoptera were collected from the Iriomote island of Okinawa prefecture, Japan. The morphological features of the specimens were characterized as having a white band on the dorsal surface of its thorax, its tegmen reduced into a tiny scale-like structure and the hindwing was absent. Ocelli was also absent and the small compound eyes not extending to apex of the head nor to the frontal face but extend further lower than the base of the antennae. When the specimens were reared in the laboratory, besides the short wing form, the long wing form began to appear in the rearing colony. In our reproductive biological study, we observed that hatching of the ootheca from the short wing female takes about 30 days, with an average of 6.6 nymphs being hatched from one ootheca. The male to female ratio of the offspring was 36:30. However, the frequency appearance of the offspring from the ootheca of the short wing female was 98.5% short wing and 1.5% long wing form. Our specimens occasionally show body polymorphism in the form of individuals having long wings instead of the usual short one. The long wing form does not show the white band on the dorsal surface of its thorax.

Deficiency of tenascin-C delays articular cartilage repair in mice.

OBJECTIVE: In human articular cartilage, tenascin-C (TN-C) expression decreases during maturation of chondrocytes, and almost disappears in adults; however, it reappears in damaged cartilage. To examine the effects of TN-C on cartilage degeneration and repair, we compared articular cartilage degeneration between wild-type (WT) and tenascin-C knockout mouse (TNKO) mice using a spontaneous osteoarthritis (OA) in aged joints and surgical OA model. In addition, we made full-thickness cartilage defects and compared the cartilage repair process between the two groups. METHODS: The surgical procedure to create degenerative OA model was performed by transecting the anterior cruciate ligament and medial collateral ligament. Full-thickness defects were created in the center of the femoral trochlea to evaluate cartilage repair. Sections of cartilage were stained with hematoxylin and eosin or safranin-O, and immunostaining for TN-C. The degrees of degeneration and repair were graded. RESULTS: In the WT surgical OA model, the articular cartilage was almost normal at 2 weeks, but safranin-O decreased staining at 4 weeks. In TNKO mice, safranin-O decreased staining at 2 weeks, and cartilage was injured intensely at 4 weeks. In the cartilage repair model, TN-C was expressed after 1 week, was strongly expressed in the upper layer of regenerated tissue after 3 weeks, and disappeared after 6 weeks. The defects were restored until 6 weeks in WT mice; however, defects in TNKO mice were filled with fibrous tissue with no cartilage-like tissue. CONCLUSIONS: This study revealed that cartilage repair in TNKO mice was significantly slower than that in WT mice and that the deficiency of TN-C progressed during cartilage degeneration.

Fibre architecture and song activation rates of syringeal muscles are not lateralized in the European starling.

The songbird vocal organ, the syrinx, is composed of two sound generators, which are independently controlled by sets of two extrinsic and four intrinsic muscles. These muscles rank among the fastest vertebrate muscles, but the molecular and morphological foundations of this rapid physiological performance are unknown. Here we show that the four intrinsic muscles in the syrinx of male European starlings (Sturnus vulgaris) are composed of fast oxidative and superfast fibres. Dorsal and ventral tracheobronchialis muscles contain slightly more superfast fibres relative to the number of fast oxidative fibres than dorsal and ventral syringealis muscles. This morphological difference is not reflected in the highest, burst-like activation rate of the two muscle groups during song as assessed with electromyographic recordings. No difference in fibre type ratio was found between the corresponding muscles of the left and right sound generators. Airflow and electromyographic measurements during song indicate that maximal activation rate and speed of airflow regulation do not differ between the two sound sources. Whereas the potential for high-speed muscular control exists on both sides, the two sound generators are used differentially for modulation of acoustic parameters. These results show that large numbers of superfast fibre types are present in intrinsic syringeal muscles of a songbird, providing further confirmation of rapid contraction kinetics. However, syringeal muscles are composed of two fibre types which raises questions about the neuromuscular control of this heterogeneous muscle architecture.

Prevention of neural tube defects by loss of function of inducible nitric oxide synthase in fetuses of a mouse model of streptozotocin-induced diabetes.

AIMS/HYPOTHESIS: Maternal diabetes during pregnancy increases the risk of congenital malformations such as neural tube defects (NTDs). Although the mechanism of this effect is uncertain, it is known that levels of nitric oxide synthase (NOS) and nitric oxide are elevated in embryos of a mouse model of diabetes. We postulated that overproduction of nitric oxide causes diabetes-induced congenital malformations and that inhibition of inducible NOS (iNOS) might prevent diabetic embryopathy. METHODS: Mice were rendered hyperglycaemic by intraperitoneal injection of streptozotocin. The incidence of congenital malformations including NTDs was evaluated on gestational day 18.5. We assessed the involvement of iNOS in diabetes-induced malformation by administering ONO-1714, a specific inhibitor of iNOS, to pregnant mice with streptozotocin-induced diabetic mice and by screening mice with iNOS deficiency due to genetic knockout (iNos(-/-)). RESULTS: ONO-1714 markedly reduced the incidence of congenital anomalies, including NTDs, in fetuses of a mouse model of diabetes. It also prevented apoptosis in the head region of fetuses, indicating that iNOS is involved in diabetes-related congenital malformations. Indeed, no NTDs were observed in fetuses of diabetic iNos(-/-) mice and the incidence of other malformations was also markedly reduced. CONCLUSIONS/INTERPRETATION: We conclude that increased iNOS activity during organogenesis plays a crucial role in the pathogenesis of diabetes-induced malformations and suggest that inhibitors of iNOS might help prevent malformations, especially NTDs, in diabetic pregnancy.

Inhibition of PMA-induced, LFA-1-dependent lymphocyte aggregation by ADP ribosylation of the small molecular weight GTP binding protein, rho.

Botulinum C3 exoenzyme specifically ADP-ribosylates a group of ras-related small molecular weight GTP-binding proteins, rho, and inhibits their biological activity. Using this enzyme, we examined the function of rho in PMA-induced activation of lymphocyte function-associated antigen-1 (LFA-1) in a B lymphoblastoid cell line, JY. Northern blot analysis revealed that among the three rho genes, rhoA mRNA was predominantly expressed in JY cells. Consistently, only one [32P]ADP-ribosylated band was found when the lysate of the cells was subjected to ADP ribosylation by C3 exoenzyme. When the cells were cultured with C3 exoenzyme, this substrate was ADP-ribosylated in situ in a time- and concentration-dependent manner. Concomitant with this ADP ribosylation, PMA-induced LFA-1/intercellular adhesion molecule (ICAM)-1-dependent aggregation of JY cells was inhibited. This inhibition was blocked by prior treatment of the enzyme with an anti-C3 monoclonal antibody, and overcome by stimulation with higher concentrations of PMA. The C3 exoenzyme-induced inhibition was not affected by shaking of the cell suspension, while inhibition of aggregation by cytochalasin B was abolished by this procedure, suggesting that the inhibitory effect of the C3 exoenzyme treatment was not due to decrease in cell motility. The C3 exoenzyme treatment affected neither protein phosphorylation in JY cells before and after PMA stimulation, nor affected surface expression of LFA-1 and ICAM-1. These results suggest that rhoA protein works downstream of protein kinase C activation linking PMA stimulation to LFA-1 activation and aggregation in JY cells.

Ectopic (subcutaneous) Paragonimus miyazakii infection in a dog.

Ectopic infection with Paragonimus miyazakii was determined to be the cause of a subcutaneous inguinal mass in a 15-month-old, male, boar-hunting dog. On histologic examination, the mass comprised granulomatous panniculitis, intralesional adult trematodes and eggs, and lymphadenitis. Extrapulmonary paragonimosis in animals is rare. This appears to be the first report in a dog of ectopic P. miyazakii infection with mature trematodes and eggs that involved the inguinofemoral lymphocenter and surrounding subcutis.

Patellar tendon reflex as a predictor of improving motor paralysis in complete paralysis due to cervical cord injury.

STUDY DESIGN: A retrospective study. OBJECTIVE: We have encountered several cases of complete sensorimotor paralysis in which patellar tendon reflex (PTR) was demonstrated approximately 3 days after injury and improvement of motor paralysis was subsequently achieved. We considered that PTR apparent in the early stage after injury may offer an index to predict improvements in motor paralysis. MATERIALS AND METHODS: A total of 142 patients assessed as ASIA Impairment Scale A on admission from 1979 to 1998 were included in the study. The patients who demonstrated PTR within 72 h after injury were classified as the PTR(+) group and those who did not constituted the PTR(-) group. With regard to the method of motor paralysis assessment at about 6 months after injury, patients assessed as ASIA Impairment Scale A or B (that is, complete motor paralysis) were classified as 'Non-recovered', whereas those assessed as ASIA Impairment Scale C, D or E (that is, showing obvious improvement of motor paralysis) were considered as 'Recovered'. RESULTS: A significant difference was noted between groups, with the Recovered group including 16 of the 17 PTR(+) patients (94.1%) and 11 of the 115 PTR(-) patients (9.6%) (P<0.0001). CONCLUSION: The results obtained indicate that motor paralysis recovery could be expected at a very high rate among patients demonstrating PTR within 72 h of injury. As all physicians should be familiar with the PTR, this seems to represent a simple and highly useful sign to predict improvements in motor paralysis during the acute stage of cervical cord injury.

Purification and characterization of antibacterial substances produced by a marine bacterium Pseudoalteromonas haloplanktis strain.

AIMS: To purify and characterize compounds with antimicrobial activity from Pseudoalteromonas haloplanktis inhibition (INH) strain. METHODS AND RESULTS: The P. haloplanktis isolated from a scallop hatchery was used to analyse antibacterial activities. Crude extracts were obtained with ethyl acetate of the cultured broth, after separation of bacterial cells, and assays against six strains of marine bacteria and nine clinically important pathogenic bacteria. The active compounds were purified from ethyl acetate extracts, by a combination of SiO(2) column and thin layer chromatography. Two active fractions were isolated, and chemical structures of two products from the major one were unambiguously identified as isovaleric acid (3-methylbutanoic acid) and 2-methylbutyric acid (2-methylbutanoic acid), by comparing their mass spectra and (1)H- and (13)C-nuclear magnetic resonance spectra to those of authentic compounds. CONCLUSIONS: In the antibacterial activity of P. haloplanktis INH strain, extra cell compounds are involucred, mainly isovaleric and 2-methylbutyric acids. SIGNIFICANCE AND IMPACT OF THE STUDY: Production of antimicrobial compounds by marine micro-organisms has been widely reported; however, the efforts not always are conducted to purification and applications of these active compounds. This study is a significant contribution to the knowledge of compounds unique from marine bacteria as potential sources of new drugs in the pharmacological industry.

Foreign-body granulomas in the trunk and extremities may simulate malignant soft-tissue tumors: report of three cases.

Three cases of foreign-body granulomas arising from soft tissues of the extremities or trunk are reported. All patients had a history of having undergone surgery 19 to 35 years ago. It was difficult to distinguish these granulomas from malignant soft-tissue tumors preoperatively by magnetic resonance (MR) images, as the tumors were over 10 cm in diameter and degenerated foreign bodies could not be detected on MR images. Finally, a histological diagnosis of foreign-body granuloma was made by preoperative or intraoperative biopsy in all cases. A palpable tumor adjacent to a previous surgery scar is therefore a warning that it might represent a granuloma, in spite of various image findings.

Cordectomy for post-traumatic syringomyelia.

We performed cordectomy, a surgical technique that is infrequently used at present, for a patient with post-traumatic syringomyelia (following complete paraplegia of both lower limbs due to dislocation fracture of the 9th thoracic vertebra), yielding a favourable result. We recommend cordectomy as a surgical technique to which spinal surgeons should give utmost consideration for patients with post-traumatic syringomyelia demonstrating progressive symptoms assumed to be attributable to the syrinx and with an anatomically transected spinal cord of the mid-to-lower thoracic vertebral level.

Histiocytic osteolysis secondary to hyperbilirubinaemia: a case report.

A 6-year-old boy with Alagille syndrome, characterised by marked hyperbilirubinaemia, presented with malunion of a pathological fracture of the femur with local bone atrophy and insufficient callus formation. During corrective osteotomy, it was noted that the femur was stained dark green, suggestive of bilirubin deposition. Histology of the resected bone revealed the presence of many histiocytes and osteoclast-like multinucleate giant cells containing bilirubin particles in the cytoplasm causing bone resorption. These findings suggest that bilirubin may activate macrophages to form osteoclast-like multinucleate giant cells, resulting in histiocytic osteolysis.

Autologous mixed lymphocyte reaction in the peripheral blood and pleural effusions of cancer patients.

T cells proliferate in response to autologous non-T cells in the autologous mixed lymphocyte reaction (AMLR). AMLR was impaired in the peripheral blood of patients with advanced lung cancer (4,159 +/- 3,878 delta cpm vs. 11,221 +/- 4,156 delta cpm for normal donors) but normal or even higher in their malignant pleural effusions (13,257 +/- 7,075 delta cpm vs. 10, 870 +/- 5,013 delta cpm for nonmalignant control effusions). Blood T cells also failed to respond to autologous effusion non-T cells, while effusion T cells strongly responded to autologous erythrocytes blood non-T cells. The presence of blood T cells did not inhibit effusion AMLR of the same patients. A subset of T cells that form rosettes with autologous erythrocytes if found to proliferate in AMLR. The number of autorosette-forming cells was lower in blood T cells of cancer patients than in blood T cells of normal donors and in effusion T cells of the patients. After enrichment of autorosette-forming cells, there was no difference in AMLR of normal blood and cancer blood and effusions. These results indicate that the loss of AMLR in the blood of cancer patients is due to a reduction of number of autoreactive T cells and not to a defect of autologous stimulator non-T cells.

Treatment of virus-induced myocardial injury with a novel immunomodulating agent, vesnarinone. Suppression of natural killer cell activity and tumor necrosis factor-alpha production.

Controversy still exists concerning the therapy for viral myocarditis which manifests a wide variety of clinical symptoms. Vesnarinone, a quinolinone derivative that was developed as a positive inotropic agent with complex actions, including phosphodiesterase inhibition and cation channel modification, has recently been confirmed to improve the prognosis of patients with chronic heart failure. However, the precise mechanism of this beneficial effect is not yet clearly understood. In this study, using a murine model of acute viral myocarditis resulting from encephalomyocarditis virus infection, survival and myocardial damage were markedly improved by treatment with vesnarinone. In contrast, survival was not improved by treatment with amrinone, a phosphodiesterase inhibitor. Although vesnarinone did not inhibit viral replication or protect myocytes from viral direct cell injury, it did inhibit the increase in natural killer cell activity after viral infection. On the other hand, amrinone failed to inhibit natural killer cell activity. Both vesnarinone and amrinone suppressed the production of tumor necrosis factor-alpha. Therefore, we postulate that vesnarinone exerted its beneficial effects through an inhibition of natural killer cell activity, and that it serves as an immunomodulator providing new therapeutic possibilities for the treatment of viral myocarditis and/or immunological disorders.

HHR23B, a human Rad23 homolog, stimulates XPC protein in nucleotide excision repair in vitro.

A protein complex which specifically complements defects of XP-C cell extracts in vitro was previously purified to near homogeneity from HeLa cells. The complex consists of two tightly associated proteins: the XPC gene product and HHR23B, one of two human homologs of the Saccharomyces cerevisiae repair gene product Rad23 (Masutani et al., EMBO J. 13:1831-1843, 1994). To elucidate the roles of these proteins in "genome-overall" repair, we expressed the XPC protein in a baculovirus system and purified it to near homogeneity. The recombinant human XPC (rhXPC) protein exhibited a high level of affinity for single-stranded DNA and corrected the repair defect in XP-C whole-cell extracts without extra addition of recombinant HHR23B (rHHR23B) protein. However, Western blot (immunoblot) experiments revealed that XP-C cell extracts contained excess endogenous HHR23B protein, which might be able to form a complex upon addition of the rhXPC protein. To investigate the role of HHR23B, we fractionated the XP-C cell extracts and constructed a reconstituted system in which neither endogenous XPC nor HHR23B proteins were present. In this assay system, rhXPC alone weakly corrected the repair defect, while significant enhancement of the correcting activity was observed upon coaddition of rHHR23B protein. Stimulation of XPC by HHR23B was found with simian virus 40 minichromosomes as well as with naked plasmid DNA and with UV- as well as N-acetoxy-2- acetylfluorene-induced DNA lesions, indicating a general role of HHR23B in XPC functioning in the genome-overall nucleotide excision repair subpathway.

Identification and characterization of XPC-binding domain of hHR23B.

hHR23B was originally isolated as a component of a protein complex that specifically complements nucleotide excision repair (NER) defects of xeroderma pigmentosum group C cell extracts in vitro and was identified as one of two human homologs of the Saccharomyces cerevisiae NER gene product Rad23. Recombinant hHR23B has previously been shown to significantly stimulate the NER activity of recombinant human XPC protein (rhXPC). In this study we identify and functionally characterize the XPC-binding domain of hHR23B protein. We prepared various internal as well as terminal deletion products of hHR23B protein in a His-tagged form and examined their binding with rhXPC by using nickel-chelating Sepharose. We demonstrate that a domain covering 56 amino acids of hHR23B is required for binding to rhXPC as well as for stimulation of in vitro NER reactions. Interestingly, a small polypeptide corresponding to the XPC-binding domain is sufficient to exert stimulation of XPC NER activity. Comparison with known crystal structures and analysis with secondary structure programs provided strong indications that the binding domain has a predominantly amphipathic alpha-helical character, consistent with evidence that the affinity with XPC is based on hydrophobic interactions. Our work shows that binding to XPC alone is required and sufficient for the role of hHR23B in in vitro NER but does not rule out the possibility that the protein has additional functions in vivo.

Two human homologs of Rad23 are functionally interchangeable in complex formation and stimulation of XPC repair activity.

XPC-hHR23B protein complex is specifically involved in nucleotide excision repair (NER) of DNA lesions on transcriptionally inactive sequences as well as the nontranscribed strand of active genes. Here we demonstrate that not only highly purified recombinant hHR23B (rhHR23B) but also a second human homolog of the Saccharomyces cerevisiae Rad23 repair protein, hHR23A, stimulates the in vitro repair activity of recombinant human XPC (rhXPC), revealing functional redundancy between these human Rad23 homologs. Coprecipitation experiments with His-tagged rhHR23 as well as sedimentation velocity analysis showed that both rhHR23 proteins in vitro reconstitute a physical complex with rhXPC. Both complexes were more active than free rhXPC, indicating that complex assembly is required for the stimulation. rhHR23B was shown to stimulate an early stage of NER at or prior to incision. Furthermore, both rhHR23 proteins function in a defined NER system reconstituted with purified proteins, indicating direct involvement of hHR23 proteins in the DNA repair reaction via interaction with XPC.